Early differentiation of Lyme from enteroviral meningitis.

BACKGROUND

Differentiating Lyme meningitis from enteroviral meningitis remains difficult because both occur mostly in the summer and early fall. This distinction is clinically important because pathogen-specific diagnostic test results are not available immediately and only patients with Lyme meningitis require parenteral antibiotic therapy.

OBJECTIVES

The objective of this study was to identify clinical and laboratory features that might help clinicians distinguish patients with Lyme meningitis from those with enteroviral meningitis.

METHODS

This cross-sectional study compared patients diagnosed with Lyme or enteroviral meningitis evaluated at a large children's hospital between January 1, 1999 and September 20, 2002.

RESULTS

Twenty-four patients with Lyme meningitis and 151 patients with enteroviral meningitis had median ages of 10.5 and 5.5 years, respectively (P < 0.0001). There was an equal proportion of boys with Lyme (63%) and enteroviral meningitis (62%; P = 1.0). The duration of symptoms before evaluation was longer for patients with Lyme meningitis (12 days) than with enteroviral meningitis (1 day; P < 0.0001). Cranial neuropathy was a presenting feature in 71% of children with Lyme meningitis. Cranial neuropathy, erythema migrans rash or papilledema occurred in 88% of patients with Lyme meningitis; no patients with enteroviral meningitis exhibited any of these findings (P < 0.0001). Lyme meningitis was unlikely when cerebrospinal fluid neutrophils exceeded 10% (negative predictive value, 99%).

CONCLUSIONS

We identified several clinical and laboratory features that may permit early differentiation of Lyme from enteroviral meningitis. These results may assist clinicians with decisions regarding additional testing and empiric antibiotic therapy.